The Internet Archive is a facility in California that keeps track of everything that's ever been on the internet. Brewster Kahle, calling himself a "digital librarian", explains the history, functionality, and process of the Internet Archive.

One of the

One of the best uses of this was when it was used to find that 'official' government weather records were being changed. Once it was pointed out, the 'official' records were restored. Of course, they may have been changed again.